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  <title>Document</title>
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  <script>
    function arr(nums, original) {
      for (let i = 0; i < nums.length; i++) {
        if (nums[i] === original) {
          original = original * 2
          return arr(nums, original)
        }
      }
      return original
    };
    console.log(arr(nums = [5, 3, 6, 1, 12], original = 3));
  </script>
</body>

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